Britannica
Sources used in this answer
How do linear, branched, and network polymers differ in structure?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
polymer
Industrial polymers are synthesized from simple compounds joined together to form long chains. For example, polyvinyl chloride is an industrial homopolymer synthesized from repeating units of vinyl chloride.
Polymers are classified by their molecular architecture, which significantly influences their physical properties and behavior.12
- Linear Polymers: These consist of monomers joined end-to-end to form a single, continuous chain. Because they lack cross-links, these molecules can pack closely together, often resulting in higher crystallinity and toughness. They typically soften or melt when heated and can dissolve in certain solvents.2134
- Branched Polymers: These feature a main chain with shorter chains branching off at intervals. This structure prevents the molecules from packing as closely as linear chains, which generally results in weaker intermolecular forces, increased flexibility, and lower crystallinity.21
- Network Polymers: These are formed when numerous branches cross-link to other chains, creating a complex, three-dimensional, chemically bonded structure. Because these chains are interconnected by strong covalent chemical bonds, they do not melt or dissolve; instead, they remain dimensionally stable until they undergo chemical decomposition. Their rigidity depends on the density of the network.241